(a) Field of the Invention
The present invention relates to an iterative receiver and a method for detecting a transmitted signal thereof.
This work was supported by the IT R&D program of MIC/IITA [2006-S-001-01, Development of adaptive radio access and transmission technologies for 4th generation mobile communications].
(b) Description of the Related Art
In a cellular mobile communication system, in order to overcome a service area limit and a subscriber capacity limit, the service area is divided into a plurality of small regions, that is, cells, and the same frequency bandwidth is used by two cells that are separated from each other so that the frequency may be reused spatially. In this instance, intercell interference is generated when the cell size is reduced so as to increase the subscriber capacity. Therefore, the receiver can accurately detect the signal by eliminating interference from the received signal. However, signal detection performance is deteriorated since the receiver cannot accurately estimate the interference.
Regarding prior art, to reduce the intercell interference, the technique of combining and detecting cell signals of a plurality of cells on the cell boundary using a maximum likelihood sequence detection (MLSD) scheme has been proposed.
However, since the Viterbi algorithm is used for the combination and detection process, system complexity is exponentially increased in proportion to the entire number of users of the cells.
As another solution for the problem of calculation complexity, iterative receiver based on the turbo principle has been proposed. However, the proposal is not applicable when no channel information is given since the proposal assumes perfect channel estimation.
Further, to reduce the intercell interference, the technique of detecting linear multi-user has been proposed. However, it increases the complexity of operation since it calculates the number of multi-users or the inverse matrix having a dimension of a spread factor.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.